1. Field of the Invention
The present invention relates to a snap-in roof rail air bag assembly for a vehicle and a method of attaching same.
2. Background Art
Use of roof rail air bag assemblies, used primarily as a means to protect vehicle passengers, is well known. Likewise, methods of attaching these air bag assemblies are also well known. Despite the widespread use of these air bag assemblies, and despite the many different means by which they are attached to the interior of a vehicle, typical attachment mechanisms have a number of inherent limitations.
One limitation is the necessity of having separate fasteners to attach the air bag assembly to the vehicle. U.S. Pat. No. 6,082,761 issued to Kato et al. on Jul. 4, 2000, discloses an air bag assembly containing a bracket with mounting holes. Separate fasteners, either threaded or push-in, are inserted through the mounting holes and then secured to the vehicle. This type of design increases the cost of the air bag assembly by requiring additional parts—i.e., fasteners—as well as the additional labor required to install the fasteners and mount the assembly to the vehicle from the side or overhead.
Stripped threads is a problem often encountered when large air bags are installed into the vehicle using threaded attachments. Proper alignment of the fasteners with the threaded holes in the vehicle frame is difficult for an operator who is trying to maneuver the large air bag assembly. Thus, misalignment is common and the likely result is stripped threads or cross-threaded attachments. Weld nuts or “u-nuts” are sometimes used as an alternative to threaded fasteners; however, these designs do not eliminate all of the problems associated with using separate fasteners in the installation process.
One attempt to overcome these problems is disclosed in U.S. Pat. No. 5,988,735 issued to Muller on Nov. 23, 1999. Muller discloses a vehicle head liner into which air bag assemblies are mounted. This eliminates the need to separately mount the air bag assemblies onto the vehicle. With this design, the air bags are installed into the vehicle when the head liner is installed, thus eliminating the need to use separate fasteners. A disadvantage of this design is that the installation of the head liner is made more difficult because of the presence of the air bag assemblies. Moreover, this design, as well as other prior art designs, all have another inherent limitation: overhead installation. Each of these designs requires operators to work with air bag assemblies over their heads, which increases overall cycle time.
Accordingly, it is desirable to provide an air bag assembly which overcomes the above referenced short comings of prior art air bag assemblies, by eliminating the need for external fasteners as well as the need for the operator to enter the vehicle or work overhead.